how do I become a contributor?

Create a giveaway, give the gift, and have the winner mark it as received.

You create a giveaway, someone random wins a giveaway, you send them the game you created the giveaway for, they mark that they received the game from you, you become a contributor.

Gifting games. 1 2

Start by reading the FAQ's.

Give away games by using the giveaway tab at the top. You can't give away games in your steam library so either steam keys from bundles or games in your inventory. Welcome to steamgifts

Make Fortix giveaways! LOTS OF THEM!

Thank you all for the answers.